Hyperuricemia complicated with acute kidney injury is associated with adverse outcomes in patients with severely decompensated acute heart failure

Abstract

Background: The relationship between the serum level of uric acid (UA) and the acute kidney injury on admission in patients with acute heart failure (AHF) remain unclear. Methods and results: A total of 1326 AHF patients were screened, and data for 1047 patients who were admitted to the intensive-care unit were analyzed. The patients were assigned to a low-UA group (UA ≤ 7.0 mg/dl, n = 569) or a high-UA group (UA > 7.0 mg/dl, n = 478) according to their UA level at admission. Acute kidney injury (AKI) at admission was defined based on the ratio of the serum creatinine value recorded on admission to the baseline creatinine value: no-AKI (n = 736) or AKI (n = 311). The patients were therefore assigned to four groups: low-UA/no-AKI (n = 428), high-UA/no-AKI (n = 308), low-UA/AKI (n = 141) and high-UA/AKI (n = 170). The high-UA patients were significantly more frequent in the AKI group than in the non-AKI group among all patients and the non-chronic kidney injury (CKD) cohort. A Kaplan-Meier curve showed a significantly lower 365-day survival rate in the high-UA/AKI group than in the other groups. The multivariate Cox regression model identified only high-UA/AKI as an independent predictor of 365-day mortality (hazard ratio [HR]: 2.511, 95% confidence interval [CI] 1.671–3.772 in all AHF patients, HR: 1.884, 95% CI 1.022–3.473 in non-CKD patients and HR: 3.546, 95% CI 2.136–5.884 in CKD patients). Conclusion: An elevated serum UA level complicated with AKI was an independent predictor of mortality in patients with severely decompensated AHF. Keywords: Acute heart failure syndrome, Uric acid, Renal function, Mortality